Canto 2 -
Ayodhyā-kāṇḍa
Chapter 21: Rāma Consoles Kausalyā and Lakṣmaṇa
Text 2.21.53

यथैव ते पुत्र पिता तथाहं गुरुः स्वधर्मेण सुहृत्तया च।
न त्वानुजानामि न मां विहाय सुदुःखितामर्हसि गन्तुमेवम्॥

yathaiva te putra pitā tathāhaṁ
guruḥ sva-dharmeṇa suhṛttayā ca
na tvānujānāmi na māṁ vihāya
suduḥkhitām arhasi gantum evam

yathā eva = like; te = Your; putra = My son; pitā = father; tathā aham = I; guruḥ = am Your guru; sva-dharmeṇa = due to my specific duty; suhṛttayā = affection; ca = and; na tvā anujānāmi = I don’t permit You [to leave]; na = not; mām = me; vihāya = leaving; suduḥkhitām = in great distress; arhasi = You should; gantum = go away; evam = like this.

My son, like Your father, I am Your guru due to my specific duty and affection. I don’t permit You [to leave]. Leaving me in great distress, You should not go away like this.1 

1 This is a summary of her previous arguments.